g-ambaro



(No Model.) 5' Sheets-Sheet 1..

P. A. GAMBARO.

GAR BRAKE.

No.. 336,911. Paten'ted Mar.

N A INVENTUR; WLTNl-:ssla: YW, Q M i .a

By falo' fior/Legal: @ff Wma@ @4 m @Mm N. PETERS, PhuwLilhagnpher,washingmn, ILC.

(No Model.) 5 Sheets-Sheet 3. P. A. GAMBARO.

GAR BRAKE.

INVENTDR:

WITNESSES;

@www JMW m N. PETERS. PPPP vmmgnpm, wnhmgmn. D. c.

(No Model.) 5 Sheets-Sheet 4.

P. A. GAMBARO.'

GAR BRAKE.

No. 336,911. 1W@ Patented Mar.z,1886.

INVENT'DR:

, .By ful? iter/Lega.'

NA FUER; Phowuxhognpher. wmmgwn, 0.o,

(No Model.) 5 Sheets-Sheet 5.

f P. A. GAMBARO.

GAR BRAKE.

fly/ Patented Mar. 2, 1886.

n. Pneus, Phmumugnpner. wnmngxa. n.c.

UNiTan STATES PATENT Ormea.

PAUL ARTHUR GAMBARO, OF PARIS, FRANCE.

cAa-BRAKE.

'Q'PECIFICATION forming part. of Letters Patent No. 336,911, dated March2, 1886. Application led December 14, 1885. Serial No. 185,549. (Nomodel.) Patented in France February 16, 1884, No. 160,378; in BelgiumFebruary 23, 1884, No. 64,255; in England February 23, 1884, No. 3,834;in Germany March 9, 1884, No.29,959; in Luxemburg March 10, 1884, No.366, and in Austria-Hungary October l0, 1884, No. 29,197 and No. 45,922.

To all whom, t may concern:

Be it known that I, PAUL ARTHUR GAMBA- RO, a citizen of the FrenchRepublic, and a resident of Paris, France, haveinvented certainImprovements in Car-Brakes, (on which patents have been granted in thefollowing countries: In France, No. 160.378, dated February 16, 1884; inBelgium, No. 64,255, dated February 23, 1884; in Germany, No. 29,959,dated March 9, 1884; in England, No. 3,834, dated February 23, 1884; inLuxemburg, No. 366, dated March 10, 1884, and in Austria- Hungary, No.29,197 and No. 45.922, dated October 10, 1884,) of which the followingis a specification.

My invention relates to-brakes primarily for railway and tram cars; andthe object is to effect the braking without the application of shoestothe wheel-treads.

The principal feature of my invention is the employment of an elastichelix wliichveinbraces a drum fixed on the car axle or wheel, and whichmay be drawn by suitable mechanism, operated either automatically ornonautomatically, until the helical band is caused to inwrap and embracethe drum tightly enough to produce the proper arnountot' friction toeffect the braking.

In the accompanying drawings 1 have shown several modes of applying andcontrolling my brake, all of which will be hereinafter fully described.

1n these drawings, Figuresl to 10 illustrate the application ot' niybrake to a car of the French pattern. Fig. 1 isa longitudinal view orelevation, taken substantially in the plane indicated by line l l inFig. 2, of the platform and runninggear ot' a car provided with mybrake. Fig. 2is a plan ofthe same. 1n these two views the right-hand orrear end of the car is shown as provided with cushion-springs for thedraw-bar and bumpers constructed dif ferently from those at theleft-hand or front end. Fig. 3 is a transverse vertical section takensubstantially in the plane indicated by line 3 3 in Fig. 2. Fig. 3 is anillustrative sectional view of one of the buffer-connections. Figs. 4and 5 are respectively an ele- -American pattern.

vation and diametrical section of one of the friction-wheels that bearon the axle-drum. Figs. 6 and 7 are two views showing the attachment ofthe windlass-chain to the helical strap of the brake. Fig. 8 is an axialsection of the axle-drum, and Fig. 9 is as to the left half an endelevation of said drum, and as to right half a transverse section ofsaine on line 9 9 in Fig. 8. Fig. 10 is an axial sectional view of theaxle-drum and friction-wheels. This View illustrates aslight variationin construction that will be hereinafter explained. Figs. 11 to 13illustrate a slightly moditied application of my brake to a car. Fig. l1is a longitudinal section taken substantially in the plane indicatedbyline 1l 11 in Fig. 12. Fig. 12 is aplan. Fig. 12 is an enlargedsectional view illustrating the mounting of the buffer and its spring,'as shown at the left hand in Fig. 12, also in Fig. 2. Fig. 12" is anenlarged sectional view illustrating the construction of thespring-holder of the buffer, as shown at the right hand in Fig. 12, alsoin Fig. 2. Fig. 13 is one-half ot' a transverse section takensubstantially on line 13 13 in Fig. 11. Figs. 14, 15, and 16 illustratethe application ot' my brake to a car-truck of the Fig. 14 is alongitudinal section. Fig. 15 is a plan or bottom View, and Fig. 16 anend elevation. Fig. 17, 18, and 19 illustrate further modifications thatwill be hereinafter described. i

Like letters of reference designate like or corresponding parts in allthe figures.

The principle of operation of my brake is as follows: Au elastic band,usually of steel, is made to encircle a drum fixed on the car-axle; butnormally the elasticity ofthe band or helix allows it to expand andstand free of the drum,

Lso that it will exert no friction on the drum when the latter rotateswithin it. If, however, a strain is put upon the end ofthe helicalband,it will be caused to contract and close on the drum and pressthereon with a force corresponding to the strain. Thus any degree ofbraking-friction desired may be applied to the axle to retard or preventits rotation. As

soon as the strain is relaxed, the elasticity of t-hem.

the helix will cause it to again expand, so as not to press upon thedrum, and the latter is free to rotate.

Referring now to Figs. l, 2. 3, and 3, I will proceed to describe myinvention as applied to acar. Let A represent the platform of arailway-car, B B the wheels, and C C the axles. D is adrum or barrelfixed on the axle, and E is the elastic band wound helically around thesame. ln this construction the brakes are controlled to some extent,aswill be explained, by the draw-bar and buffers. The draw-bar is notcontinuous, and each draw-bar operates independently on the brakes.

Referring, for further illustration, to Figs. 4, 5, 6, 7, 8, 9, and l0,F F/ are two frictionwheels, which are fixed on an axle mountedrotatively in the lower end of a lever, G, fulcru med at a on thecar-frame. To the respective wheels F F', which have elongated bosses,Figs.l 4, 5, and 10, are attached the chains or flexible connections bb, which are connected to the ends of the elastic band E. A spring, H,connected at one end to the upper end of lever G and at the other end tothe car-body. tends at all times to keep the wheels F F pressed intofrictional contact with the drum D. When the car is moving toward theleft in Fig. l, and the car-wheels and frictionwheels are rotating inthe direction of the arrows, the chains b b will be wound upon thebosses of the frictionwheels to an extentsuicient to cause the band E toembrace the drum D with a force commensurate to the strength of spring Hand the leverage with which it acts.

In order that the brakes may not be set when the car is undertraction-that is, when there is a pulling strain on the draw-bar-Iprovide the means I will now describe, referring first to the lefthandend of Figs. l and 2. and incidentally to Fig. 122 The drawbar I passesthrough a box, c, in which is placed a cushion-spring, d. Loose on thedraw-bar is a washenplate, e, which rests againsta shoulder on the box,and serves as an abutment for one end of spring d. On the draw-bar is asleeve, f, which may play through the in ner contracted end of thespring-box, and which is compelled to move longitudinally with thedraw-bar by ak ey behind said sleeve. Normally there is a space betweenthe sleevef and the washer plate e of from ten to twenty millimeters,and the pull on the draw-bar does not begin to compress thecushion-spring until the draw-bar has moved outlongitudinally to thisextent. To the inner end ofthe draw-bar is coupled a bar'or compensator,J, and to the inner end of this compensator are coupled two bars, K K,which extend back, and are connected or coupled at their other ends tothe two levers G G at opposite ends of the caraxle or to a tie orcross-bar, G', connecting S0 far as the use of two drums D, levers G,te., for each axle is concerned, this is a mere duplication, and neednot be particularly considered. Vhere two sets are used, as indicated inFig. 2, two bars K will be required to connect the'two levers Gto thedraw-bar. For simplicity of description, I will refer to but one set. Itwill be observed that the spring H tends to retract the draw-bar I andpress the wheels F F into lfrictional contact with drum D, and that therst movement of the draw-bar will be to distend spring H and draw thewheels F F out of contact with the drum. The spring H offers only aresistance of about ten kilograms. Whatever the movement of the drawbarmay be before the cnshionspring begins to offer resistance to the draft,it is very little, and there will be no appreciable shock when thesleevef comes in contact with the washer e. While there is traction onthe draw-bar the brake will be free; but if there is a cessation of thedraft or traction on the draw-bar it comes back to its original positionwith the aid, iirst, of the cushion-spring and afterward of the springH. The wheels F F will be pressed against the drum D, and the latterwill rotate said wheels, wind up the chains b b', and cause the band Eto tightly embrace the drum.

In Figs. 4 and 5 one of the friction-wheels is shown detached andenlarged. The holes in it are designed to receive suitable eyebolts forthe attachment of one of the chains b or b', as the case may be. The useof two wheels has the advantages that the space between them spans thespace occupied by the Spirallywound band E on the drum and gives an evenbearing. Qne chain is'attached to each wheel.

'No matter in which direction the drum rotates,

the chains will be wound upon the wheels.

As before stated, the draw-bar is not continuous, but the draft oneither bar will set the brakes on both axles. This is effected throughthe medium of the connecting-rods or draftrodsL L. (Seen best in Fig.1.) These rods cross each other, and connect the lever G at one axle ofthe car with the corresponding lever at the other axle, the lowercouplings of the rods to the levers being slotted, so Vthat one rod willnot interfere with the operation of the other. This will bereadilyunderstood.

In order that the coming together of the buffers may remove or releasethe brakes, the

Ibuffer M is provided with a spring-box, c', a

cushion-spring, d', a washerplate, e, and a shouldenf', corresponding tothe similar parts connected with the draw-bar I, only, of course,arranged to operate inversely. To the inner prolonged end of the bufferis coupled a lever, N, fulcrumed at g, the other end of which lever iscoupled to the compensator J, as clearly shown in Fig. 2. Each buffer issimilarly connected to the compensator, and the levers N are coupledwith slotted connections in order that the buffer and draw-bar may actindependently on the brake, and not interfere.

In order that the brakes may be thrown off by hand, I provide a lever,O, which is arranged under Ylever N fulcrumed at the same point, g, andconnected to the compensator K. Thus the brakes may be thrown offindepend ICC ently by the draw-bar, by the buffers, and by hand.

At the right-hand end of the car in Figs. 1 and 2 I have shown amodified arrangement wherein the ordinary elliptical cushion-spring. d,is employed in lieu ofthe volute springs d and d shown at the left hand.

In order to get the required movement of the draw-bar before thecushion-spring comes into play, the bar is given some playin the holderc of the spring d by means of a slot in the said holder, and a key whichpasses through the draw-bar and engages said slot. The required play ofthe buffer is effected by similar means, as indicated in Figs. 1, 2, and3.

Figs. 8 and 9 show, det-ached, the drum D, and illustrate the details ofits construction. The drum is made in halves, so as to be readilyapplied to the axle, and the frictional surface h is made of softcast-iron. This surface is in the ferm of two half-cylinders, the endsof which are housed in grooves in the body h and cap h of the drum.` Iusually bolt the drum to the earwheel, instead of to the axle.

Fig. 10 simply shows grooves in which the edges of the wheels FF bear.This somewhat increases the frictional contact.

Figs. 11, 12, vand 13 show an application of my brake, which will now bedescribed. This form of the brake is automatic, with direct command andwit-h alimited predetermined braking-power. The general construction andarrangement ofthe draw-bar, buffers,

cushions, springs, drums D, and elastic band E are the same as in Figs.l, 2, and 3. The means for effecting the braking is somewhat modified.In the lower ends of levers G are mounted pulleys F, around which passthe bights of chains bf, connected with the elastic band E. The chain bis connected at its ends to the ends of the band. To the lever, aboveits fulcrnm, is attached a spring, II', which tends to draw the pulley Faway from the drum D, and thus put tension on the band E and cause it tofrictionally embrace the drum.

To prevent the drums in their rotation from carrying around with themthe bands E, to the end of said bands are coupled chains z' i jj', whichare brought to and attached to a suspender, k, pivoted atl totheear-body. This device keeps the bands properly in place on the drums atall times. Normally the brake is closed; but it may be thrown off byhand by means of a handle, G,attached to lever G. The levers G are alsoconnected to the drawbar and buffers in a manner substantially the sameas that shown in Figs. 1 and 2. It will be seen that in thisconstruction the action of the lever G is direct on the band E, and doesnot act through the intermediary of frictionwheels, as in theconstruction first described.

Figs. 14, 15, 16, 17, 18, and 19 show the application of the foregoingprinciples to trucks similar to those in use on American railwaycars.The drums D are fixed to the wheels. The elastic steel bands E aremounted on these drums, as before described. Each ofthe two extremitiesof the elastic band E is provided with a chain which is capable of beingwound on a barrel, P, fixed on the same shaft, Q, with a friction-wheel,F. The shaftsQare mounted in the ends of swinging levers 1t R, thewheels F being iu the planes of the carwheels B. A spring, H, connectsthe levers R R to the car-body, and by its tension keeps the wheels Fdrawn into frietional contact with the wheel-treads. The rotation of thecar-wheels under these conditions rotates the wheels F, winds up thechains which connect the barrels l? with the ends of the band E, andtends to tighten the band E on the drum D. This tension is pnt on bothends of the band E. It is immaterial in which direction the car moves,the brakes will be set the same.

In this application of the brake it is controlled by theibllowing-described mechanism: Let us suppose that the car is moving inthe direction indicated by the arrow on the earwheel B at the left handin Fig. 14. The draw-bar l (see the plan view, Fig. 17,which shows theend of the car-platform) is provided with two cushion-springs of verydifferent tension, S being the stronger and .s the weaker. Suppose thatthe spring s is compressed under the effort necessary to move thefrictionwheels F out of contact with the car-wheel treads, and that thiseffort is inferior to that necessary to draw the empty car. On the otherhand, the elements of this spring s are such that the movement of thedraw-bar corresponding to this compression may be sufficient `to drawthe friction-wheels out of contact by the intermediation of thesuspended levers R R and the ccnnecting-rods m and n, arranged as shownin Fig. l-t.

The tappets T T on the continuous drawbar engage the ends of the leversR R, as clearly seen in Fig. 14, and the movement ofthe draw-bar is thusmade to operate the connected levers through the intermediary of therods m n. lt may be remarked that all these movements ofcommand arebrought into the axis of the car by means of bridle-rods K, and that if'Figs. 14 and l5 represent one of the two trucks'or bogies of the samecar the movements of the conuecting-rods'm n may be transmitted to thesimilar mechanism on the other truck by rods supported at their middles.It will be sufficient to attach these rods at any suitable point aboveor below the fulcrums ofthe levers RRin such a manner that it is notindispensable to provide for their opration acontinuons draw-bar. y Whenthe cars come together, and the buffers M are driven in, they act torelease the brakes in a manner similar to that described with referenceto Figs. 1 and 2. In Fig. 17 theconstruction is shown. Each buffer M hastwo cushionsprings, S s', of unequal strength, similar to the springs Ss of the draw-bar.

a horizontal lever, N, which is ful'crumed-at IOO iro

ISO

The buffer communicates its motion to a bar, U, throughg. This bar Uisseen in Fig. 14, and it is arranged directly under the draw-bar.

It will .be seen by reference to Fig. 14 that Vis a rocking levermounted on the truckframe, and that the bar U is coupled to its upperend by a slotted connection. Io the lever V is coupled the rods n, whichconnect it with the levers It R above and below the fulcrum, and the rodm, which connects this rocklever with its neighbor at the other end ofthe truck. The spring H is connected to the rocking lever V,and actsthrough it on the two levers It R.

I make the barrels Pas small diametrically as is practicable, and thewheels F as large diametrically asis practicable. This is in order thatI mayobtain all the advantage of leverage possible.

In lieu of arranging t-he wheels F to come into peripheral contact withthe car-wheels, it will be practicable to arrange them to contact withsurface ofthe drum D, as in the iirstdescribed constructions. In Figs.18 and 19 (the former of which is a sectional elevation and the latter aplan) I have shown this arrangement. The two friction-wheels F F aremounted on the same axis, which is rotatively mounted in `a pendentlever, G If the direction of rotation is that indicated by the arrows inFig. 18, the chain b, connected with the free end of the elastic band E,will be bound on the b oss of wheel F', in friction-al contact with thedrum, while the other wheel, F, by its bearings on the drum becomes, ina sense, a fixed point of resistance by reason of the tension of thechain b. The contraction ofthe band E is thus effected, and the moreenergetically it acts on the drum the greater will be the prcssureof thewheels F F on the drum. Consequently this latter pressure will increasemore and more and draw the band E tighter and tighter. This arrangementproduces a more energetic braking effect than the preceding. The settingand throwing oii' of the brakes are effect-ed by moving the wheels F Finto and out ot'contact with the drum D through the medium of the leverG. The required movement of this lever is effected easily by means of alever, o, which connects the levers G of the two opposite brake deviceson the same axle, which bar is acted on by a cam, W, on the draw-bar I.Ont-he end of the lever, or what is the same, on an arm, p, branchingfrom the tiebar 0, is acounter-weight, X, and under said arm is aretractingspri ng, q. The cam W acts on a friction'bowl, r, on the baro. Vhen the draw-bar isin repose, as in Fig. 18, the friction wheelsrest on the drum by 'virtue of their gravity; but the endwise movementof the draw-bar causes the cam WV tudepress the lever back of thefulcrum a, and thus lift said wheels out of contact. It will beunderstood that the expansion oi' the band E normally is such that thisslight movement of the friction-wheels outof contact will not sufiice tocontract the band on the drum, and the same may be said of the similarconstructions shown in Figs. 1 and 14. The friction-wheels might ofcourse contact with the ends instead of with the convex surfaces of thedrums.

I have described my brake as applied to railway-cars; but it may beapplied to all corr structions where brakes are required.

I do not Wish to limit myself to the precise construction andarrangement herein shown, as these may be varied to some extent withoutmaterially departing from my invention.

I am aware that it is not new to apply a. chain to a drum by winding thesame spirally around the drum, the same to serve as a brake by applyinga pulling strain to one end of the chain, the other end being fixed. Myelastic band frees itself from the dru m,when the strain is removed fromit, by its own elasticity, and stands free and out of contact with thesurface of the drum, as has been explained, thus avoiding chafing andwear which would otherwise result.

Having thus described my invention, I claim- 1. The combination, with arotativelymounted shaft or drum, the speed of which is to be regulatedby a brake, of an elastic helicoidal band encompassing suchrotativelymounted part` but having, when not under tension, an internaldiameter a little greater than that of the part it encompasses,wherebythe said brake maybe set by pulling on the ends of said bar, and thuscontracting it, as set forth. v

2. The combination, with a rotativclymounted part-as a drum, foreXample-ofan elastic spiral or helicoidal band encompassing saidrotating part, and mechanism, substan tially as described, for applyinga pulling strain4 to the ends of said elastic band,whereby it is made tocontract and tightly embrace the said rotating part, substantially asset forth.

3. 'The combination, with a rotativelymounted part-as a drum, forexample--of an elastic spiral or helical band encompassing said rotatingpart, two frictionwheels fixed on a common shaft and connected,respectivel y, by chains or other flexible connectors with theends of said elastic band, and means, substantially as described, forputting said frictionwheels into peripheral contact with the rotatingpart, substantially as set forth.

4. The combination, in a car-brake, of a drum, D, fixed to thecar-wheel, either directly or indirectly, as described, an elasticspiral or helicoidalband, E, ,encompassing said drum, twofriction-wheels on the same axis. connected, respectively,with the endsof band E, a lever, G, which carries the said friction-wheels, and whichis fulcrumed on the car-frame, a spring, H, which holds thefriction-wheels in peripheral contact with the drum D, and means,substantially as described, whereby the said friction-wheels are movedout of contact with the drum through the medium of the draw-bar, as setforth.

5. The combination, in a car-brake, of the drum D, attached directly orindirectly to ioo IZO

the oar-wl1eel, and rotating in unison therewith, the spiral elasticband E, encompassing said drum, the friction-wheels F F', mountedrotatively in the pendent end of a lever, G, andconnected,respectively,to the ends of the band E, as described, the saidlever G fulcrumed ou the earframe, the spring I-I, connected to a lixedpoint at one end and to the lever G, as described, whereby it tends todraw the Wheels F F into peripheral. Contact with the drum, t'nedraw-bar I, connected directly or i ndireetl y to the lever G, asdescribed, and. provided with a collar or shoulder, f, thecushion-spring d, its box c, and the washerplate e, all arrangedsubstantially as described, whereby the draw-bar is caused in itslongitudinal movement to act against the tension of spring H, to releasethe brake before it acts to'oompress the cushion-spring, substantiallyas set forth.

6. The combination, with the draw-bar I and the braking mechanism,constructed substantiallyv as described, of shouldered buffer M, theCushion spring d, its box c', and Washer plate e', and the lever N,fnlcrumed at 25 g, and provided with slotted connections to the drawlbarand buffer, substantially as and for the purposes set forth.

In Witness whereof I have hereunto signed my name in the presence of twosubscribing 3o Witnesses.

PAUL ARTHUR GAMBARO.

. Witnesses:

EDWARD P. MACLEAN, AMAND RITTER..

